Today, in many modern manufacturing facilities, modular conveyor systems are extensively utilized to transport articles to and from various workstations during all stages of production. In recent years, manufacturers using production lines with conveyors as an integral component of the material handling system, have realized reasonably significant gains in productivity and resource utilization. As a result, modular conveyor systems have become even more widely implemented, and have been adapted to meet an even wider scope of the material handling needs of producers of a multitude of consumer and industrial goods, especially in the processed food industry. Furthermore, adaptation of existing modular conveyors for increased efficiency have become more of a viable alternative to the design of a completely new conveyor system.
However, notwithstanding recent developments and advancements in conveyor design, further improvements in material handling efficiency and conveyor adaptation are desired. For example, some articles requiring conveyor transport often have smooth or slick surfaces. Further, modular conveyors in use today, especially in the food industry, are almost exclusively constructed of rigid plastic links or modules. Such plastic is inherently smooth in surface texture to maintain sanitary requirements. Accordingly, slippage frequently occurs between the transported article and the surface of the conveyor, especially when both the article and conveyor surface are smooth. Understandably, this leads to reduced material handling efficiency whenever such product slippage occurs.
In an effort to minimize product slippage, some prior art modular conveyors have been constructed with at least some links comprising solid elastomeric material, such as rubber. Advantageously, users of such links have realized a reduction in product slippage due to the increased frictional characteristic of the elastomer. However, the use of such elastomer links has proven to have significant shortcomings as well. For example, elastomer is a comparatively weak material, and links composed of elastomer tend to weaken and rapidly wear as they are subjected to the stress and strain associated with movement along the conveyor path. Moreover, when elastomer links are used in a modular conveyor that traverses a curve or bend, the weakening of the links is further hastened. Furthermore, solid elastomer links lack the ability to smoothly interact with each other and the conveyor frame in an efficient, slidable relationship, as is necessary when the conveyor path traverses a bend. Instead, the elastomer links, due to their high frictional quality, necessarily must shift with respect to each other with greater resistance, further contributing to the weakening of the links as well as generally jerky conveyor movement.
Another approach in the prior art, adopted in an effort to improve conveyor belt material handling efficiency, has been to construct some of the modular links to include upstanding protrusions to provide a further degree of driving and positional support for articles placed upon the conveyor. For example, U.S. Pat. No. 4,953,693 to Draebel, owned by the assignee of the present invention, discloses the provision of upstanding fins on the legs of modular conveyor links. The fins are capable of being constructed in a variety of heights for positively engaging articles on the conveyor. Additionally, links with these upstanding fins can be installed in a variety of positions on the conveyor belt so as to create compartments, channels, and the like. Even so, this system of providing projections as a component of the modular links themselves lacks the capability of being adaptable to changing material handling needs. For example, if material handling requirements of a user change in such a way so as to necessitate the transport of differently sized or shaped articles, the whole conveyor belt may have to be restructured or replaced.
Similarly, U.S. Pat. No. 3,602,364 to Maglio et al. discloses a broad teaching of using high friction elements on a belt. Specifically, Maglio teaches the concept of utilizing suction cups to provide additional frictional capability for smooth, flat belt conveyors. Nonetheless, the Maglio system does not teach removable frictional elements that are easily removable, and thus readily selectively positionable on the conveyor where needed. Further, a belt of the Maglio type has the additional limitation of lacking the capability to traverse bends.
The U.S. Pat. No. 4,629,063 to Hodlewsky et al. discloses the utilization of resilient gripping members on a flexible system of dual conveying chains for lifting products from one height to another. However, this system similarly has the limitation of not being readily adaptable to handling differently sized and shaped products. This inflexibility is a result of the fixed distance across which the dual chains are permanently mounted. Thus, although the resilient members may be capable of grasping a limited range of different products, this system is still limited in use to situations where flexible and adaptable material handling is not required.
The U.S. Pat. No. 5,224,583 to Palmaer et al. discloses the concept of providing rolling inserts for modular link conveyors. However, these inserts are designed to add additional stability to the conveyor rather than enhance material handling capabilities.
Thus, it is clear that a need exists for a conveyor with improved material handling capabilities featuring an article engaging insert that is readily positionable on the conveyor where needed. Also, such an insert exhibiting increased frictional properties is desirable. Such a conveyor would be capable of quick adaptation in the field to accommodate the transportation of articles of different sizes, shapes and textures. Such a conveyor would further be able to provide for positive engagement of articles being transported in an economically more efficient, more productive and more reliable manner.